Coated article having low-e coating with ir reflecting layer(s) and doped titanium oxide dielectric layer(s) and method of making same

ABSTRACT

A coated article includes a low emissivity (low-E) coating having at least one infrared (IR) reflecting layer of a material such as silver, gold, or the like, and at least one high refractive index layer of or including titanium oxide and at least one additional metal. A doped titanium oxide layer(s) is designed and deposited in a manner so as to be amorphous or substantially amorphous (as opposed to crystalline) in the low-E coating, so as to better withstand optional heat treatment (HT) such as thermal tempering and reduce haze. The high index layer may be a transparent dielectric high index layer in preferred embodiments, which may be provided for antireflection purposes and/or color adjustment purposes, in addition to having thermal stability.

This application relates to a coated article including a low emissivity(low-E) coating having at least one infrared (IR) reflecting layer of amaterial such as silver, gold, or the like, and at least one highrefractive index layer of or including doped titanium oxide (e.g., TiO₂doped with at least one additional element). The doped titanium oxidelayer(s) is designed and deposited in a manner so as to be amorphous orsubstantially amorphous (as opposed to crystalline) in the low-Ecoating, so as to better withstand optional heat treatment (HT) such asthermal tempering. The high index layer may be a transparent dielectrichigh index layer in preferred embodiments, which may be provided forantireflection purposes and/or color adjustment purposes, in addition tohaving thermal stability. In certain example embodiments, the low-Ecoating may be used in applications such as monolithic or insulatingglass (IG) window unit, vehicle windows, of the like.

BACKGROUND AND SUMMARY OF EXAMPLE EMBODIMENTS OF THE INVENTION

Coated articles are known in the art for use in window applications suchas insulating glass (IG) window units, vehicle windows, monolithicwindows, and/or the like.

Conventional low-E coatings are disclosed, for example and withoutlimitation, in U.S. Pat. Nos. 6,576,349, 9,212,417, 9,297,197,7,390,572, 7,153,579, and 9,403,345, the disclosures of which are herebyincorporated herein by reference.

Certain low-E coating utilize at least one transparent dielectric layerof titanium oxide (e.g., TiO₂), which has a high refractive index (n),for antireflection and/or coloration purposes. See for example U.S. Pat.Nos. 9,212,417, 9,297,197, 7,390,572, 7,153,579, and 9,403,345. Althoughhigh refractive index dielectric materials such as TiO₂ are known andused in low-E coatings, these materials are not thermally stable and aretypically not heat stable after tempering process of about 650 C for 8minutes, due to film crystallization (or change in crystallinity) inas-deposited or post-tempering state, which may in turn induce thermalor lattice stress on adjacent layers in the film stack. Such stress canfurther cause change in physical or material properties of the stack andhence impact on the Ag layer, which results in deteriorated low E stackperformance. In other words, conventional TiO₂ layers are typicallysputter-deposited so as to realize a crystalline structure, which leadsto damage to the stack upon HT as explained above.

Example embodiments of this invention solve these problems by providinga high index doped titanium oxide layer for use in low-E coatings thatboth has a high refractive index (n) and is substantially stable uponheat treatment (HT).

“Heat treatment” (HT) and like terms such as “heat treating” and “heattreated”, such as thermal tempering, heat strengthening, and/or heatbending, as used herein means heat treating the glass substrate andcoating thereon at temperature of at least 580 degrees C. for at least 5minutes. An example heat treatment is heat treating at temperature ofabout 600-650 degrees C. for at least 8 minutes.

In example embodiments of this invention, a coated article includes alow emissivity (low-E) coating having at least one infrared (IR)reflecting layer of a material such as silver, gold, or the like, and atleast one high refractive index dielectric layer of or including dopedtitanium oxide (e.g., TiO₂ doped with at least one additional elementsuch as Sn, ZnSn, Y, Zr, and/or Ba). The doped titanium oxide layer(s)is designed and deposited in a manner so as to be amorphous orsubstantially amorphous (as opposed to crystalline) in the low-Ecoating, so as to better withstand optional heat treatment (HT) such asthermal tempering. For example, it has been found thatsputter-depositing the doped titanium oxide layer(s) in an oxygendepleted atmosphere results in the doped titanium oxide layer beingdeposited in an amorphous or substantially amorphous (as opposed tocrystalline) state, which in turn allows the layer and overall coatingto be much more stable upon HT. The high index layer(s) may be atransparent dielectric high index layer in preferred embodiments, whichmay be provided for antireflection purposes, transmission, and/or coloradjustment purposes, in addition to having thermal stability. In certainexample embodiments, the low-E coating may be used in applications suchas monolithic or insulating glass (IG) window units, vehicle windows, orthe like.

In an example embodiment of this invention, there is provided a coatedarticle including a coating supported by a glass substrate, the coatingcomprising: a first transparent dielectric layer on the glass substrate;an infrared (IR) reflecting layer comprising silver on the glasssubstrate, located over at least the first transparent dielectric layer;a second transparent dielectric layer on the glass substrate, locatedover at least the IR reflecting layer; and wherein at least one of thefirst and second transparent dielectric layers is amorphous orsubstantially amorphous, and comprises an oxide of Ti doped with atleast one of Sn, SnZn, Zr, Y, and Ba, and wherein metal content of theamorphous or substantially amorphous layer comprises from about 70-99.5%Ti and from about 0.5-30% of at least one of Sn, SnZn, Zr, Y, and Ba(atomic %).

In another example embodiment of this invention, there is provided acoated article including a coating supported by a glass substrate, thecoating comprising: a first transparent dielectric layer on the glasssubstrate; an infrared (IR) reflecting layer comprising silver on theglass substrate, located over at least the first transparent dielectriclayer; a second transparent dielectric layer on the glass substrate,located over at least the IR reflecting layer; and wherein at least oneof the first and second transparent dielectric layers is amorphous orsubstantially amorphous, and comprises an oxide of Ti and Ba, andwherein metal content of the amorphous or substantially amorphous layercomprises from about 30-70% Ti and from about 30-70% Ba (atomic %).

In another example embodiment of this invention, there is provided amethod of making a coated article including a coating supported by aglass substrate, the method comprising: sputter depositing a firsttransparent dielectric layer on the glass substrate; sputter-depositingan infrared (IR) reflecting layer comprising silver on the glasssubstrate, located over at least the first transparent dielectric layer;sputter-depositing a second transparent dielectric layer on the glasssubstrate, located over at least the IR reflecting layer; and wherein atleast one of the first and second transparent dielectric layers issputter-deposited so as to be amorphous or substantially amorphous, andcomprise an oxide of Ti and at least one of Sn, SnZn, Zr, Y, and Ba. Theat least one of the first and second transparent dielectric layerssputter-deposited, so as to be amorphous or substantially amorphous, maybe sputter-deposited in an oxygen depleted atmosphere so that adifference in radii for metals during sputtering causes lattice disorderleading to amorphous or substantially amorphous structure of the layer.

BRIEF DESCRIPTION OF THE DRAWINGS

This patent or application file contains at least one drawing executedin color. Copies of this patent or patent application publication withcolor drawing(s) will be provided by the Office upon request and paymentof the necessary fee.

FIG. 1 is a cross sectional view of a coated article according to anexample embodiment of this invention.

FIG. 2 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index titanium oxidelayer versus wavelength (nm) in both as-coated (AC) and post-HT (HT)states.

FIG. 3 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index Zr-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states.

FIG. 4 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index Sn-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states.

FIG. 5 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index Sn-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states when the Sn-doped titanium oxide layer was sputterdeposited in an atmosphere containing 70% oxygen (O₂) gas and 30% argon(Ar) gas (sccm).

FIG. 6 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index Sn-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states when the Sn-doped titanium oxide layer was sputterdeposited in an atmosphere containing 20% oxygen (O₂) gas and 80% argon(Ar) gas (sccm).

FIG. 7 is a chart setting forth oxidation states and ionic radii ofvarious elements.

FIG. 8 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index Ba-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states.

FIG. 9 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index Y-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states.

FIG. 10 is a percentage (%) versus wavelength (nm) graph plottingtransmission (T) %, glass side reflection (G) %, and film sidereflection (F) % of a layer stack including a high index SnZn-dopedtitanium oxide layer versus wavelength (nm) in both as-coated (AC) andpost-HT (HT) states.

FIG. 11 is a cross sectional view of a coated article according toanother example embodiment of this invention.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS OF THE INVENTION

Referring now to the drawings in which like reference numerals indicatelike parts throughout the several views.

Coated articles herein may be used in applications such as monolithicwindows, IG window units such as residential windows, patio doors,vehicle windows, and/or any other suitable application that includessingle or multiple substrates such as glass substrates.

High refractive index material such as TiO₂ with low or no lightabsorption in the visible range is often used in low-E coatings inwindow applications. However, TiO₂ is typically not heat stable after athermal tempering process such as involving HT at about 650 C for 8minutes, due to film crystallization (or change in crystallinity) inas-deposited or post-tempering state, which may in turn induce thermalor lattice stress on adjacent layers in the film stack. Such a stresscan further cause change in physical or material properties of the stackand hence impact on the IR reflecting Ag based layer, which results indeteriorated low E stack performance.

FIG. 2 illustrates that TiO₂ is not thermally stable, and thus is notheat treatable from a practical point of view. FIG. 2 is a percentage(%) versus wavelength (nm) graph plotting transmission (T) %, glass sidereflection (G) %, and film side reflection (F) % of a layer stackincluding a high index titanium oxide layer versus wavelength (nm) inboth as-coated (AC) and post-HT states. The layer stack was glass/TiO₂(27 nm)/ZnO (4 nm)/Ag (11 nm)/NiTiNbO_(x)(2.4 nm)/ZnSnO (10 nm)/ZnO (4nm)/SiN (10 nm), where the ZnO layers were doped with Al in thisComparative Example (CE) stack. Thus, the AC curves are prior to HT, andthe HT curves are after heat treatment at about 650 degrees C. for abouteight minutes. In FIG. 2, at the right side where the curves are listed,the top three are as coated (AC) which means prior to the HT, and thebottom three are following the heat treatment and thus are labeled “HT.”FIG. 2 shows that the layer stack with the crystalline TiO₂ is notthermally stable and thus not practically heat treable. In particular,the Comparative Example (CE) of FIG. 2 shows a significant shift in theIR range of the transmission and reflectance spectra, and increases inemissivity and haze were also found. In FIG. 2, in the wavelength areafrom about 1500 to 2400 nm, there was a shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of about 6%; there was a shift due to HT from the “AC G”(glass side reflectance, as coated prior to HT) curve to the “HT G”(glass side reflectance, after HT) curve of about 12-14%; and there wasa shift due to HT from the “AC F” (film side reflectance, as coatedprior to HT) curve to the “HT F” (film side reflectance, after HT) curveof about 12-13%. Overall, taken together in combination, there is asignificant shift in transmission and reflection spectra upon HT whichindicates a lack of thermal stability.

Example embodiments of this invention provide for a high index dopedtitanium oxide dielectric layer(s) designed to suppress crystallinity,irrespective of HT conditions such as thermal tempering. A high indexdoped titanium oxide dielectric layer 2 for use in low-E coatings isprovided that has a high refractive index (n) and is amorphous orsubstantially amorphous and thus substantially stable upon heattreatment (HT). In example embodiments of this invention, a coatedarticle includes a low emissivity (low-E) coating having at least oneinfrared (IR) reflecting layer 4 of a material such as silver, gold, orthe like, and at least one high refractive index dielectric layer 2 (andpossibly 6) of or including doped titanium oxide (e.g., TiO₂ doped withat least one additional element such as Sn, ZnSn, Y, Zr, and/or Ba). Thedoped titanium oxide layer(s) 2 (and possibly 6) is designed anddeposited in a manner so as to be amorphous or substantially amorphous(as opposed to crystalline) in the low-E coating, so as to betterwithstand optional heat treatment (HT) such as thermal tempering. Forexample, comparing FIGS. 5 and 6, it has been found thatsputter-depositing the doped titanium oxide layer(s) 2, 6 in an oxygendepleted atmosphere results in the doped titanium oxide layer 2, 6 beingdeposited in an amorphous or substantially amorphous (as opposed tocrystalline) state, which in turn surprisingly and unexpectedly allowsthe layer and overall coating to be more stable upon HT. It has beenfound that the difference in atomic radii between Ti and its dopant(s)(e.g., between Ti and Sn, or Ti and Ba, or Ti and Y, etc.) can beenhanced and adjusted by changing the oxidation states of both atoms byreducing oxygen content in the sputtering gas atmosphere used whensputter-depositing the layer, and this oxygen depletion in thesputtering atmosphere causes a lattice disorder (e.g., disruption in thelattice formation) and impedes the formation of crystals in thedeposited doped titanium oxide layer, thereby leading to amorphous orsubstantially amorphous structure for sputter deposited layer(s) 2, 6which is stable even at high temperature thermal tempering. A largedifference in ionic radii of Ti and dopant ions can disrupt the latticeand impede crystalline growth of the compound. The ionic radii depend onoxidation state and coordination number (e.g., see FIG. 7). Low oxygenconditions in the sputtering gaseous atmosphere force Ti into a loweroxidation state and/or lower coordination which in turn results in alarger difference in ionic radii with the dopant (e.g., Sn, SnZn, Ba, orY). For example, FIG. 6 illustrates that when the oxygen gas contentused when sputtering a Sn-doped titanium oxide layer is dropped to 20%(e.g., remainder argon gas) the coating is much more thermally stablethan when the oxygen content was at 70% in FIG. 5. FIG. 7 shows that 6coordination at 4+ oxidation states Ti and Sn have fairly close ionicradii of 61 and 69 pm (difference of 8 pm) which provides forsignificant crystalline growth under normal deposition oxidationconditions, but when the oxidation states change to +2 upon oxygendepletion Ti and Sn have very different ionic radii of 86 and 118 pm(difference of 32 pm) so as to impede crystalline growth. The oxygendepletion may also or instead cause Ti to move to the 4 coordination,which will also result in a large difference in ionic radii between Tiand Sn as shown in FIG. 7. As a result, the doped titanium oxidelayer(s) 2, 6 sputter-deposited in an oxygen depleted atmosphere isdeposited in an amorphous or substantially amorphous state due to thelarge difference in ionic radii and lattice disruption and thus hasthermal stability upon optional HT such as thermal tempering or heatbending. It will be appreciated that doped titanium oxide layer 2(and/or 6) may be substoichiometric in certain example embodiments ofthis invention, so as to be only partially oxided, due to the oxygendepletion used when depositing the layer 2 (and/or 6). The high indexlayer(s) 2, 6 may be a dielectric high index layer in preferredembodiments, which may be provided for antireflection purposes,transmission, and/or color adjustment purposes, in addition to havingthermal stability. In certain example embodiments, the low-E coating maybe used in applications such as monolithic or insulating glass (IG)window units, vehicle windows, or the like.

“Substantially amorphous” as used herein means majority amorphous, andmore amorphous than crystalline. For instance, “substantially amorphous”includes at least 60% amorphous, at least 80% amorphous, at least 90%amorphous, and fully amorphous. The amorphous or substantially amorphoushigh index doped titanium oxide layer(s) 2, 6 may be a transparentdielectric high index layer, and may be oxided and/or nitrided, inpreferred embodiments, and is provided for antireflection purposesand/or color adjustment purposes, in addition to having thermalstability. When the doped titanium oxide layer(s) 2, 6 is/are nitride,it is preferably that the nitrogen content be small such as from 0-10%,more preferably from 0-5% (atomic %).

Thus, doped titanium oxide layer 2 (and possibly 6) discussed herein maybe sputter-deposited in an oxygen depleted atmosphere in order torealize and amorphous or substantially amorphous sputter depositedlayer. In certain example embodiments of this invention, no more than50% of the gaseous atmosphere in which the doped titanium oxide layer 2(and possibly 6) is sputter deposited is made up of oxygen gas, morepreferably no more than 40%, even more preferably no more than 35%, andmost preferably no more than 25%. The remainder of the gas in theatmosphere may be an inert gas such as argon gas, or the like. Forexample, an example 20% oxygen atmosphere in the sputtering chamber(s)is made up of 20% oxygen gas and 80% argon gas. Small amounts of othergas may also be included, intentionally or unintentionally.

FIG. 1 is a cross sectional view of a coated article according to anexample embodiment of this invention. The coated article includes glasssubstrate 1 (e.g., clear, green, bronze, or blue-green glass substratefrom about 1.0 to 10.0 mm thick, more preferably from about 1.0 mm to6.0 mm thick), and a multi-layer coating (or layer system) provided onthe substrate 1 either directly or indirectly. As shown in FIG. 1, theexample low-E coating may be of or include high index amorphous orsubstantially amorphous transparent dielectric layer 2 based on dopedtitanium oxide as discussed herein, zinc oxide and/or zinc stannateinclusive contact layer 3 (e.g., ZnO_(x) where “x” may be about 1; orZnAlO_(x)), IR (infrared) reflecting layer 4 including or of silver,gold, or the like, upper contact layer 5 of or including an oxide of Niand/or Cr (e.g., NiCrO_(x)) or other suitable material, and a dielectricovercoat of or including dielectric layer 6 that may be a medium indexlayer such as zinc oxide or zinc stannate, or may be a high index layersuch as the doped titanium oxide discussed herein, optional medium indexlayer 7 of or including zinc oxide, tin oxide, and/or zinc stannate orother suitable material, and dielectric layer 8 of or including siliconnitride and/or silicon oxynitride or other suitable material. Thesilicon nitride inclusive layers (e.g., layer 8) may further include Al,oxygen, or the like, and the zinc oxide based layers may also includetin and/or aluminum. Other layers and/or materials may also be providedin the coating in certain example embodiments of this invention, and itis also possible that certain layers may be removed or split in certainexample instances. For example, a zirconium oxide layer or a AlSiBO_(x)layer (not shown) could be provided directly over and contacting siliconnitride layer 8. As another example, a medium index layer such assilicon nitride could be provided between the glass substrate 1 and highindex layer 2. As another example, two silver based IR reflectinglayers, spaced apart by a dielectric layer stack including tin oxide forinstance, may be provided and the overcoat and/or undercoat of FIG. 1may be used therein. Moreover, one or more of the layers discussed abovemay be doped with other materials in certain example embodiments of thisinvention. This invention is not limited to the layer stack shown inFIG. 1, as the FIG. 1 stack is provided for purposes of example only inorder to illustrate an example location(s) for a high index dopedtitanium oxide layer(s) 2 and/or 6 discussed herein.

In monolithic instances, the coated article includes only one substratesuch as glass substrate 1 (see FIG. 1). However, monolithic coatedarticles herein may be used in devices such as IG window units forexample. Typically, an IG window unit may include two or more spacedapart substrates with an air gap defined therebetween. Example IG windowunits are illustrated and described, for example, in U.S. Pat. Nos.5,770,321, 5,800,933, 6,524,714, 6,541,084 and US 2003/0150711, thedisclosures of which are all hereby incorporated herein by reference.For example, the coated glass substrate shown in FIG. 1 may be coupledto another glass substrate via spacer(s), sealant(s) or the like with agap being defined therebetween in an IG window unit. In certain exampleinstances, the coating may be provided on the side of the glasssubstrate 1 facing the gap, i.e., surface #2 or surface #3. In otherexample embodiments, the IG window unit may include additional glasssheets (e.g., the IG unit may include three spaced apart glass sheetsinstead of two).

High index transparent dielectric layer 2 (and layer 6 when of dopedtitanium oxide discussed herein) preferably has a refractive index (n,measured at 550 nm) of at least 2.12, more preferably of at least 2.20,more preferably of at least 2.25. These layers may optionally include asmall amount of nitrogen such as no greater than 15%, more preferably nogreater than 10%, and most preferably no greater than 5% nitrogen(atomic %). Titanium oxide (e.g., TiO₂) is sputter deposited so as to becrystalline under normal sputtering conditions which involve high oxygengas content. However, crystalline titanium oxide layers in low-Ecoatings are problematic because they are unstable upon HT such asthermal tempering.

High index transparent dielectric layer 2 (and layer 6 when of dopedtitanium oxide discussed herein) is based on titanium oxide andpreferably includes titanium oxide (e.g., TiO₂ or TiO_(x) where x isfrom 1.5 to 2.0, possibly from 1.6 to 1.97) doped with one or more ofSn, ZnSn, Y, Zr, and/or Ba. In certain example embodiments of thisinvention, doped titanium oxide layer 2 and/or 6 has a metal content offrom about 70-99.5% Ti, more preferably from about 80-99% Ti, still morepreferably from about 87-99% Ti, and from about 0.5 to 30% dopant, morepreferably from about 1-20% dopant, and most preferably from about 1-13%dopant (atomic %), where the dopant is of or includes one or more of Sn,ZnSn, Y, Zr, and/or Ba. It has been found that these dopant amountssuffice for providing sufficient lattice mismatch upon oxygen depletiondiscussed herein, and also are low enough to allow the layer to havesufficiently high refractive index (n).

Transparent dielectric lower contact layer 3 may be of or include zincoxide (e.g., ZnO), zinc stannate, or other suitable material. The zincoxide of layer 3 may contain other materials as well such as Al (e.g.,to form ZnAlO_(x)) or Sn in certain example embodiments. For example, incertain example embodiments of this invention, zinc oxide layer 3 may bedoped with from about 1 to 10% Al (or B), more preferably from about 1to 5% Al (or B), and most preferably about 2 to 4% Al (or B). The use ofzinc oxide 3 under the silver in layer 4 allows for an excellent qualityof silver to be achieved. Zinc oxide layer 3 is typically deposited in acrystalline state. In certain example embodiments (e.g., to be discussedbelow) the zinc oxide inclusive layer 3 may be formed via sputtering aceramic ZnO or metal rotatable magnetron sputtering target.

Infrared (IR) reflecting layer 4 is preferably substantially or entirelymetallic and/or conductive, and may comprise or consist essentially ofsilver (Ag), gold, or any other suitable IR reflecting material. Thesilver of IR reflecting layer 4 may be doped with other material(s),such as with Pd, Zn, or Cu, in certain example embodiments. IRreflecting layer 4 helps allow the coating to have low-E and/or goodsolar control characteristics such as low emittance, low sheetresistance, and so forth. The IR reflecting layer may, however, beslightly oxidized in certain embodiments of this invention. Multiplesilver based IR reflecting layers 4 may be provided, spaced apart inlow-E coating by at least one dielectric layer, in double or triplesilver stacks including doped titanium oxide layers discussed herein incertain example embodiments of this invention.

Upper contact layer 5 is located over and directly contacting the IRreflecting layer 4, and may be of or include an oxide of Ni and/or Cr incertain example embodiments. In certain example embodiments, uppercontact layer 5 may be of or include nickel (Ni) oxide, chromium/chrome(Cr) oxide, or a nickel alloy oxide such as nickel chrome oxide(NiCrO_(x)), or other suitable material(s) such as NiCrMoO_(x), NiCrMo,Ti, NiTiNbO_(x), TiO_(x), metallic NiCr, or the like. Contact layer 5may or may not be oxidation graded in different embodiments of thisinvention. Oxidation grading means that the degree of oxidation in thelayer changes through the thickness of the layer so that for example acontact layer may be graded so as to be less oxidized at the contactinterface with the immediately adjacent IR reflecting layer 4 than at aportion of the contact layer further or more/most distant from theimmediately adjacent IR reflecting layer. Contact layer 5 may or may notbe continuous in different embodiments of this invention across theentire IR reflecting layer 4.

Other layer(s) below or above the illustrated FIG. 1 coating may also beprovided. Thus, while the layer system or coating is “on” or “supportedby” substrate 1 (directly or indirectly), other layer(s) may be providedtherebetween. Thus, for example, the coating of FIG. 1 may be considered“on” and “supported by” the substrate 1 even if other layer(s) areprovided between layer 2 and substrate 1. Moreover, certain layers ofthe illustrated coating may be removed in certain embodiments, whileothers may be added between the various layers or the various layer(s)may be split with other layer(s) added between the split sections inother embodiments of this invention without departing from the overallspirit of certain embodiments of this invention. For example and withoutlimitation, silicon nitride layer 5 may be removed.

While various thicknesses may be used in different embodiments of thisinvention, example thicknesses and materials for the respective layerson the glass substrate 1 in the FIG. 1 embodiment may be as follows,from the glass substrate outwardly (e.g., the Al content in the zincoxide layer and the silicon nitride layers may be from about 1-10%, morepreferably from about 1-5% in certain example instances). Thickness arein units of angstroms (Å).

TABLE 1 (Example Materials/Thicknesses; FIG. 1 Embodiment) PreferredMore Layer Range (Å) Preferred (Å) Example (Å) Doped TiO_(x) (layer 2)40-500 Å 150-350 Å  270 Å ZnO or ZnAlO_(x) (layer 3) 10-240 Å 35-120 Å 40 Å Ag (layer 4) 40-160 Å 65-125 Å 110 Å Contact (layer 5)  10-70 Å 20-50 Å  34 Å ZnSnO/doped TiO_(x) (layer 6) 30-350 Å 80-200 Å 100 Å ZnOor ZnAlO_(x) (layer 7) 10-240 Å 35-120 Å  40 Å Si_(x)N_(y) (layer 8)50-250 Å 80-180 Å 100 Å

In certain example embodiments of this invention, coated articles herein(e.g., see FIG. 1) may have the following low-E (low emissivity), solarand/or optical characteristics set forth in Table 2 when measuredmonolithically.

TABLE 2 Low-E/Solar Characteristics (Monolithic) Characteristic GeneralMore Preferred Most Preferred R_(s) (ohms/sq.): <=11.0 <=10 <=9 E_(n):<=0.2 <=0.15 <=0.10 T_(vis) (%) >=50 >=60 >=70

While high index transparent dielectric doped titanium oxide layer 2(and possibly 6) is shown and described in connection with the low-Ecoating of FIG. 1 above, this invention is not so limited. Dopedtitanium oxide high index transparent dielectric layers (e.g., layer 2)described herein may be used as a high index layer(s) in any suitablelow-E coating either above or below an IR reflecting layer(s). One ormore of such doped titanium oxide layers 2 may be provided in anysuitable low-E coating. For example and without limitation, amorphous orsubstantially amorphous doped titanium oxide layer 2 as described aboveand/or herein may be used to replace any high index (e.g., TiO_(x) orTiO₂) layer in any of the low-E coatings in any of U.S. Pat. Nos.9,212,417, 9,297,197, 7,390,572, 7,153,579, 9,365,450, and 9,403,345,all of which are incorporated herein by reference.

FIG. 11 is a cross sectional view of a coated article according toanother example embodiment of this invention. FIG. 11 is similar to FIG.1, except that in the FIG. 11 embodiment a medium index (n) layer 23 ofor including material such as silicon nitride or zinc oxide is providedbetween and directly contacting the glass substrate 1 and the dopedtitanium oxide layer 2, and a low index layer 21 of a material such asSift is provided in place of layer 8. It is noted that doped titaniumoxide as discussed herein is used for the layer immediately abovecontact layer 5 in the FIG. 11 embodiment.

Examples according to certain example embodiments of this invention areas follows.

Example 1

Example 1 was a low-E coating on a glass substrate according to the FIG.1 embodiment, for comparing to FIG. 2 above. The Example 1 layer stackwas glass/TiSnO_(x) (27 nm)/ZnO (4 nm)/Ag (11 nm)/NiTiNbO_(x)(2.4nm)/ZnSnO (10 nm)/ZnO (4 nm)/SiN (10 nm), where the ZnO layers weredoped with Al. Example 1 was the same coating stack as the ComparativeExample (CE) described above regarding FIG. 2, except that in Example 1the TiO₂ layer of the CE was replaced with Sn-doped titanium oxide(TiSnO_(x)). The high index layer 2 was titanium oxide doped with tin(TiSnO_(x)) in Example 1. The oxygen depleted atmosphere in which theTiSnO_(x) layer 2 was sputter deposited contained 20% oxygen gas and 80%argon gas (4 sccm O₂ and 16 sccm Ar). Power applied to the Ti target was500 W, and power applied to the Sn target was 50 W. Metal content of theTiSnO_(x) layer 2 was 88% Ti and 12% Sn (atomic %). The coating ofExample 1 had a normal emissivity (En) of 0.068. The TiSnO_(x) layer 2of Example 1 had a refractive index (n), at 550 nm, of 2.27. FIGS. 4 and6 show the data of Example 1, before and after HT, and should becompared to the CE of FIG. 2. Note that FIGS. 4 and 6 are the same, butthat FIG. 6 is downsized and provided next to FIG. 5 for purposes ofcomparison. In FIGS. 2, 4 and 6 at the right side where the curves arelisted, the top three are “as coated” (AC) which means prior to the HT,and the bottom three are following the heat treatment and thus arelabeled “HT.” Thus, the AC curves are prior to HT, and the HT curves areafter heat treatment at about 650 degrees C. for about eight minutes.The TiSnO_(x) layer 2 was amorphous or substantially amorphous both asdeposited as well as following the HT.

Comparing FIG. 4 (and FIG. 6) to the Comparative Example (CE) in FIG. 2,significant unexpected differences are demonstrated resulting from thedoping of the titanium oxide layer 2 with tin. In FIG. 2, in thewavelength area from about 1500 to 2400 nm, there was a shift due to HTfrom the “AC T” (transmission, as coated prior to HT) curve to the “HTT” (transmission, after HT) curve of about 6%; there was a shift due toHT from the “AC G” (glass side reflectance, as coated prior to HT) curveto the “HT G” (glass side reflectance, after HT) curve of about 12-14%;and there was a shift due to HT from the “AC F” (film side reflectance,as coated prior to HT) curve to the “HT F” (film side reflectance, afterHT) curve of about 12-13%. Overall, taken together in combination, thereis a significant shift in transmission and reflection spectra upon HTwhich indicates a lack of thermal stability. The Comparative Example(CE) of FIG. 2 shows a significant shift in the IR range of thetransmission and reflectance spectra, and increases in emissivity andhaze were also found. In contrast, upon doping the titanium oxide layerwith tin and depositing TiSnO_(x) layer 2 in an oxygen depletedatmosphere, FIG. 4 shows that in the wavelength area from about 1500 to2400 nm there was very little shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of less than 4%; there was very little shift due to HTfrom the “AC G” (glass side reflectance, as coated prior to HT) curve tothe “HT G” (glass side reflectance, after HT) curve of less than 5%; andthere was very little shift due to HT from the “AC F” (film sidereflectance, as coated prior to HT) curve to the “HT F” (film sidereflectance, after HT) curve of less than 7 or 8%. These much smallershifts due to HT result from the layer being in amorphous orsubstantially amorphous form due to the oxygen depleted atmosphere inwhich it was sputtered, and demonstrate thermal stability and heattreability of the coating. Accordingly, comparing FIG. 4 to FIG. 2, itcan be seen that Example 1 was surprisingly and unexpectedly improvedcompared to the CE with respect to thermal stability and heattreatability (e.g., thermal tempering).

Example 2

Example 2 (FIG. 5) had the same layer stack as Example 1 (FIGS. 4 and 6)above, with the sole difference being that the TiSnO_(x) layer 2 inExample 2 was sputter deposited in a gaseous atmosphere containing 70%oxygen gas whereas the TiSnO_(x) layer 2 in Example 1 was sputterdepositing in a gaseous atmosphere containing 20% oxygen gas. The highindex layer 2 was titanium oxide doped with tin (TiSnO_(x)) in both ofExamples 1-2. The oxygen depleted atmosphere in which the TiSnO_(x)layer 2 was sputter deposited in Example 1 contained 20% oxygen gas and80% argon gas (4 sccm O₂ and 16 sccm Ar), but in Example 2 theatmosphere was modified to contain 70% oxygen gas and 30% argon gas (14sccm O₂ and 6 sccm Ar). Power applied to the Ti and Sn targets, the HT,and the metal content of the layer 2, were all the same in Examples 1and 2. It can be seen by comparing FIG. 5 (Example 2 with 70% oxygen gasin sputtering atmosphere) to FIG. 6 (Example 1 with 20% oxygen gas insputtering atmosphere), that the reduced oxygen gas in the sputteringatmosphere in FIG. 6 (Example 1) provided for significantly improvedresults over FIG. 5 (Example 2). FIG. 6 (like FIG. 4) shows that forExample 1 with 20% O₂ in the wavelength area from about 1500 to 2400 nmthere was very little shift due to HT from the “AC T” (transmission, ascoated prior to HT) curve to the “HT T” (transmission, after HT) curveof less than 4%; there was very little shift due to HT from the “AC G”(glass side reflectance, as coated prior to HT) curve to the “HT G”(glass side reflectance, after HT) curve of less than 5%; and there wasvery little shift due to HT from the “AC F” (film side reflectance, ascoated prior to HT) curve to the “HT F” (film side reflectance, afterHT) curve of less than 7 or 8%. However, FIG. 5 shows that for Example 2with an increased 70% O₂ in the wavelength area from about 1500 to 2400nm there was a higher shift due to HT from the “AC T” (transmission, ascoated prior to HT) curve to the “HT T” (transmission, after HT) curveof at least 6 4%; there was a much higher shift due to HT from the “ACG” (glass side reflectance, as coated prior to HT) curve to the “HT G”(glass side reflectance, after HT) curve of at least 14%; and there wasa much higher shift due to HT from the “AC F” (film side reflectance, ascoated prior to HT) curve to the “HT F” (film side reflectance, afterHT) curve of at least 16%. These much larger shifts in FIG. 5 forExample 2, compared to FIG. 6 for Example 1, due to HT result from thelayer in Example 2 being much more crystalline due to the increasedoxygen in the sputtering atmosphere in which the layer was sputtered,and demonstrate thermal instability for Example 2. Example 2 also hadincreased haze, compared to Example 1, both before and after the HT.Accordingly, comparing Example 1, Example, 2, and the ComparativeExample of FIG. 2, it can be seen that the reduced oxygen gas in thesputtering atmosphere in Example 1 provides for unexpected andsurprising results with respect to improved thermal stability,improved/reduced haze, and the ability to achieve an amorphous orsubstantially amorphous doped titanium oxide layer.

Example 3

Example 3 was a low-E coating on a glass substrate according to the FIG.1 embodiment, for comparing to FIG. 2 above. The Example 3 layer stackwas glass/TiYO_(x)(27 nm)/ZnO (4 nm)/Ag (11 nm)/NiTiNbO_(x)(2.4nm)/ZnSnO (10 nm)/ZnO (4 nm)/SiN (10 nm), where the ZnO layers weredoped with Al. Example 3 was the same coating stack as Example 1 and theComparative Example (CE) described above regarding FIG. 2, except thatin Example 3 the high index layer 2 was Y-doped titanium oxide(TiYO_(x)). The high index layer 2 was titanium oxide doped with yttrium(TiYO_(x)) in Example 3, and sputter deposited in an oxygen depletedatmosphere. Metal content of the TiYO_(x) layer was 95% Ti and 5% Sn(atomic %). The composition ratio of the TiYO_(x) was Y:Ti:Ocorresponding to 5:95:245 (atomic). The TiYO_(x) layer 2 of Example 3had a refractive index (n), at 550 nm, of 2.42. FIG. 9 shows the data ofExample 3, before and after HT, and should be compared to the CE of FIG.2. In FIGS. 2 and 9 at the right side where the curves are listed, thetop three are “as coated” (AC) which means prior to the HT, and thebottom three are following the heat treatment and thus are labeled “HT.”Thus, the AC curves are prior to HT, and the HT curves are after heattreatment at about 650 degrees C. for about eight minutes. The TiYO_(x)layer 2 was amorphous or substantially amorphous both as deposited aswell as following the HT.

Comparing FIG. 9 to the Comparative Example (CE) in FIG. 2, significantunexpected differences are demonstrated resulting from the doping of thetitanium oxide layer 2 with yttrium (Y). In FIG. 2, in the wavelengtharea from about 1500 to 2400 nm, there was a shift due to HT from the“AC T” (transmission, as coated prior to HT) curve to the “HT T”(transmission, after HT) curve of about 6%; there was a shift due to HTfrom the “AC G” (glass side reflectance, as coated prior to HT) curve tothe “HT G” (glass side reflectance, after HT) curve of about 12-14%; andthere was a shift due to HT from the “AC F” (film side reflectance, ascoated prior to HT) curve to the “HT F” (film side reflectance, afterHT) curve of about 12-13%. Overall, taken together in combination, thereis a significant shift in transmission and reflection spectra upon HTwhich indicates a lack of thermal stability. The Comparative Example(CE) of FIG. 2 shows a significant shift in the IR range of thetransmission and reflectance spectra, and increases in emissivity andhaze were also found. In contrast, upon doping the titanium oxide layerwith Y, FIG. 9 shows that in the wavelength area from about 1500 to 2400nm there was very little shift due to HT from the “AC T” (transmission,as coated prior to HT) curve to the “HT T” (transmission, after HT)curve of less than 4%; there was very little shift due to HT from the“AC G” (glass side reflectance, as coated prior to HT) curve to the “HTG” (glass side reflectance, after HT) curve of less than 5 or 6%; andthere was very little shift due to HT from the “AC F” (film sidereflectance, as coated prior to HT) curve to the “HT F” (film sidereflectance, after HT) curve of less than 6 or 7%. These much smallershifts in Example 3 (compared to the CE) due to HT result from theY-doped titanium oxide layer 2 of Example 3 being in amorphous orsubstantially amorphous form, and demonstrate thermal stability and heattreability of the coating. Accordingly, comparing FIG. 9 to FIG. 2, itcan be seen that Example 3 was surprisingly and unexpectedly improvedcompared to the CE with respect to thermal stability and heattreatability (e.g., thermal tempering).

Example 4

Example 4 was a low-E coating on a glass substrate according to the FIG.1 embodiment, for comparing to FIG. 2 above. The Example 4 layer stackwas glass/TiBaO_(x)(27 nm)/ZnO (4 nm)/Ag (11 nm)/NiTiNbO_(x)(2.4nm)/ZnSnO (10 nm)/ZnO (4 nm)/SiN (10 nm), where the ZnO layers weredoped with Al. Example 4 was the same coating stack as Example 1 and theComparative Example (CE) described above regarding FIG. 2, except thatin Example 4 the high index layer 2 was titanium oxide barium(TiBaO_(x)). The high index layer 2 was titanium oxide supplemented withbarium (TiBaO_(x)) in Example 4, and sputter deposited in an oxygendepleted atmosphere. The composition ratio of the TiBaO_(x) was Ba:Ti:Ocorresponding to 0.98:1:3.36. FIG. 8 shows the data of Example 4, beforeand after HT, and should be compared to the CE of FIG. 2. In FIGS. 2 and8 at the right side where the curves are listed, the top three are “ascoated” (AC) which means prior to the HT, and the bottom three arefollowing the heat treatment and thus are labeled “HT.” Thus, the ACcurves are prior to HT, and the HT curves are after heat treatment atabout 650 degrees C. for about eight minutes. The TiBaO_(x) layer 2 wasamorphous or substantially amorphous both as deposited as well asfollowing the HT.

Comparing FIG. 8 to the Comparative Example (CE) in FIG. 2, significantunexpected differences are demonstrated resulting from the providing ofthe barium in the titanium oxide layer 2. In FIG. 2, in the wavelengtharea from about 1500 to 2400 nm, there was a shift due to HT from the“AC T” (transmission, as coated prior to HT) curve to the “HT T”(transmission, after HT) curve of about 6%; there was a shift due to HTfrom the “AC G” (glass side reflectance, as coated prior to HT) curve tothe “HT G” (glass side reflectance, after HT) curve of about 12-14%; andthere was a shift due to HT from the “AC F” (film side reflectance, ascoated prior to HT) curve to the “HT F” (film side reflectance, afterHT) curve of about 12-13%. Overall, taken together in combination, thereis a significant shift in transmission and reflection spectra upon HTwhich indicates a lack of thermal stability. The Comparative Example(CE) of FIG. 2 shows a significant shift in the IR range of thetransmission and reflectance spectra, and increases in emissivity andhaze were also found. In contrast, upon providing Ba in the titaniumoxide layer, FIG. 8 shows that in the wavelength area from about 1500 to2400 nm there was very little shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of less than 3%; there was very little shift due to HTfrom the “AC G” (glass side reflectance, as coated prior to HT) curve tothe “HT G” (glass side reflectance, after HT) curve of less than 4%; andthere was very little shift due to HT from the “AC F” (film sidereflectance, as coated prior to HT) curve to the “HT F” (film sidereflectance, after HT) curve of less than 3%. These much smaller shiftsin Example 4 (compared to the CE) due to HT result from the BaTi oxidelayer 2 of Example 4 being in amorphous or substantially amorphous form,and demonstrate thermal stability and heat treability of the coating.Accordingly, comparing FIG. 8 to FIG. 2, it can be seen that Example 4was surprisingly and unexpectedly improved compared to the CE withrespect to thermal stability and heat treatability (e.g., thermaltempering).

It will be appreciated that while the Ba can be used as a dopant andadded in small amounts to the titanium oxide layer, Ba can also have alarger percentage as in Example 4. Thus, in certain example embodimentsof this invention, metal content of the TiBaO_(x) layer may be from30-70% Ti, more preferably from 40-60% Ti, and from 30-70% Ba, and morepreferably from 40-60% Ba.

Example 5

Example 5 was a low-E coating on a glass substrate according to the FIG.1 embodiment, for comparing to FIG. 2 above. The Example 5 layer stackwas glass/TiZnSnO_(x)(27 nm)/ZnO (4 nm)/Ag (11 nm)/NiTiNbO_(x)(2.4nm)/ZnSnO (10 nm)/ZnO (4 nm)/SiN (10 nm) where the ZnO layers were dopedwith Al. Example 5 was the same coating stack as Example 1 and theComparative Example (CE) described above regarding FIG. 2, except thatin Example 5 the high index layer 2 was ZnSn-doped titanium oxide(TiZnSnO_(x)). The high index layer 2 was titanium oxide doped with ZnSnin Example 5, and sputter deposited in an oxygen depleted atmospherecontaining 30% oxygen gas and the remainder argon gas. Sn and Zn contentwas approximately the same. The TiZnSnO_(x) layer 2 of Example 5 had arefractive index (n), at 550 nm, of 2.17. FIG. 10 shows the data ofExample 5, before and after HT, and should be compared to the CE of FIG.2. In FIGS. 2 and 10 at the right side where the curves are listed, thetop three are “as coated” (AC) which means prior to the HT, and thebottom three are following the heat treatment and thus are labeled “HT.”Thus, the AC curves are prior to HT, and the HT curves are after heattreatment at about 650 degrees C. for about eight minutes. TheTiZnSnO_(x) layer 2 was amorphous or substantially amorphous both asdeposited as well as following the HT.

Comparing FIG. 10 to the Comparative Example (CE) in FIG. 2, significantunexpected differences are demonstrated resulting from the doping of thetitanium oxide layer 2 with Sn and Zn. In FIG. 2, in the wavelength areafrom about 1500 to 2400 nm, there was a shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of about 6%; there was a shift due to HT from the “AC G”(glass side reflectance, as coated prior to HT) curve to the “HT G”(glass side reflectance, after HT) curve of about 12-14%; and there wasa shift due to HT from the “AC F” (film side reflectance, as coatedprior to HT) curve to the “HT F” (film side reflectance, after HT) curveof about 12-13%. Overall, taken together in combination, there is asignificant shift in transmission and reflection spectra upon HT whichindicates a lack of thermal stability. The Comparative Example (CE) ofFIG. 2 shows a significant shift in the IR range of the transmission andreflectance spectra, and increases in emissivity and haze were alsofound. In contrast, upon doping the titanium oxide layer with Zn and Snin Example 5, FIG. 10 shows that in the wavelength area from about 1500to 2400 nm there was very little shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of less than 3%; there was very little shift due to HTfrom the “AC G” (glass side reflectance, as coated prior to HT) curve tothe “HT G” (glass side reflectance, after HT) curve of less than 2%; andthere was very little shift due to HT from the “AC F” (film sidereflectance, as coated prior to HT) curve to the “HT F” (film sidereflectance, after HT) curve of less than 3%. These much smaller shiftsin Example 5 (compared to the CE) due to HT result from the SnZn-dopedtitanium oxide layer 2 of Example 5 being in amorphous or substantiallyamorphous form, and demonstrate thermal stability and heat treability ofthe coating. Accordingly, comparing FIG. 10 to FIG. 2, it can be seenthat Example 5 was surprisingly and unexpectedly improved compared tothe CE with respect to thermal stability and heat treatability (e.g.,thermal tempering).

Example 6

Example 6 was a low-E coating on a glass substrate according to the FIG.1 embodiment, for comparing to FIG. 2 above. The Example 6 layer stackwas glass/TiZrO_(x)(27 nm)/ZnO (4 nm)/Ag (11 nm)/NiTiNbO_(x)(2.4nm)/ZnSnO (10 nm)/ZnO (4 nm)/SiN (10 nm), where the ZnO layers weredoped with Al. Example 6 was the same coating stack as Example 1 and theComparative Example (CE) described above regarding FIG. 2, except thatin Example 6 the high index layer 2 was Zr-doped titanium oxide(TiZrO_(x)). The high index layer 2 was titanium oxide doped withzirconium (TiZrO_(x)) in Example 6, and sputter deposited in an oxygendepleted atmosphere. FIG. 3 shows the data of Example 6, before andafter HT, and should be compared to the CE of FIG. 2. In FIGS. 2 and 3at the right side where the curves are listed, the top three are “ascoated” (AC) which means prior to the HT, and the bottom three arefollowing the heat treatment and thus are labeled “HT.” Thus, the ACcurves are prior to HT, and the HT curves are after heat treatment atabout 650 degrees C. for about eight minutes. The TiZrO_(x) layer 2 wasamorphous or substantially amorphous both as deposited as well asfollowing the HT.

Comparing FIG. 3 to the Comparative Example (CE) in FIG. 2, significantunexpected differences are demonstrated resulting from the doping of thetitanium oxide layer 2 with Zr. In FIG. 2, in the wavelength area fromabout 1500 to 2400 nm, there was a shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of about 6%; there was a shift due to HT from the “AC G”(glass side reflectance, as coated prior to HT) curve to the “HT G”(glass side reflectance, after HT) curve of about 12-14%; and there wasa shift due to HT from the “AC F” (film side reflectance, as coatedprior to HT) curve to the “HT F” (film side reflectance, after HT) curveof about 12-13%. Overall, taken together in combination, there is asignificant shift in transmission and reflection spectra upon HT whichindicates a lack of thermal stability. The Comparative Example (CE) ofFIG. 2 shows a significant shift in the IR range of the transmission andreflectance spectra, and increases in emissivity and haze were alsofound. In contrast, upon doping the titanium oxide layer with Zr inExample 6, FIG. 3 shows that in the wavelength area from about 1500 to2400 nm there was very little shift due to HT from the “AC T”(transmission, as coated prior to HT) curve to the “HT T” (transmission,after HT) curve of less than 3%; there was very little shift due to HTfrom the “AC G” (glass side reflectance, as coated prior to HT) curve tothe “HT G” (glass side reflectance, after HT) curve of less than 4%; andthere was very little shift due to HT from the “AC F” (film sidereflectance, as coated prior to HT) curve to the “HT F” (film sidereflectance, after HT) curve of less than 4 or 5%. These much smallershifts in Example 6 (compared to the CE) due to HT result from theZr-doped titanium oxide layer 2 of Example 6 being in amorphous orsubstantially amorphous form, and demonstrate thermal stability and heattreability of the coating. Accordingly, comparing FIG. 3 to FIG. 2, itcan be seen that Example 6 was surprisingly and unexpectedly improvedcompared to the CE with respect to thermal stability and heattreatability (e.g., thermal tempering).

In an example embodiment of this invention, there is provided a coatedarticle including a coating supported by a glass substrate, the coatingcomprising: a first transparent dielectric layer on the glass substrate;an infrared (IR) reflecting layer comprising silver on the glasssubstrate, located over at least the first transparent dielectric layer;a second transparent dielectric layer on the glass substrate, locatedover at least the IR reflecting layer; and wherein at least one of thefirst and second transparent dielectric layers is amorphous orsubstantially amorphous, and comprises an oxide of Ti doped with atleast one of Sn, SnZn, Zr, Y, and Ba, and wherein metal content of theamorphous or substantially amorphous layer comprises from about 70-99.5%Ti and from about 0.5-30% of at least one of Sn, SnZn, Zr, Y, and Ba(atomic %).

In the coated article of the immediately preceding paragraph, metalcontent of the amorphous or substantially amorphous layer may comprisefrom about 80-99% Ti and from about 1-20% of at least one of Sn, SnZn,Zr, Y, and Ba (atomic %).

In the coated article of any of the preceding two paragraphs, metalcontent of the amorphous or substantially amorphous layer may comprisefrom about 87-99% Ti and from about 1-13% of at least one of Sn, SnZn,Zr, Y, and Ba (atomic %).

In the coated article of any of the preceding three paragraphs, theamorphous or substantially amorphous layer may have a refractive index(n) of at least 2.12, more preferably of at least 2.20, and mostpreferably of at least 2.25 (at 550 nm).

In the coated article of any of the preceding four paragraphs, thecoating may be a low-E coating and have a normal emissivity (E_(n)) ofno greater than 0.2, more preferably no greater than 0.10.

In the coated article of any of the preceding five paragraphs, theamorphous or substantially amorphous layer may comprise one or more of:(i) an oxide of Ti and Sn, and a metal content of from about 70-99.5% Tiand from about 0.5-30% Sn (atomic %), which map optionally furthercomprise Zn; (ii) an oxide of Ti and Sn, and a metal content comprisingfrom about 80-99% Ti and from about 1-20% Sn (atomic %); (iii) an oxideof Ti, Sn, and Zn; (iv) an oxide of Ti and Y, and a metal contentcomprising from about 70-99.5% Ti and from about 0.5-30% Y (atomic %),more preferably from about 80-99% Ti and from about 1-20% Y (atomic %);(v) an oxide of Ti and Ba, and a metal content comprising from about70-99.5% Ti and from about 0.5-30% Ba (atomic %), more preferably fromabout 80-99% Ti and from about 1-20% Ba (atomic %); and/or (vi) an oxideof Ti and Zr, and a metal content comprising from about 70-99.5% Ti andfrom about 0.5-30% Zr (atomic %), more preferably from about 80-99% Tiand from about 1-20% Zr (atomic %).

In the coated article of any of the preceding six paragraphs, the firstdielectric layer may be said amorphous or substantially amorphous layerand is located between the glass substrate and the IR reflecting layer,and may be in direct contact with the glass substrate.

In the coated article of any of the preceding seven paragraphs, thecoating may comprise an overcoat including a layer comprising siliconnitride.

In the coated article of any of the preceding eight paragraphs, thecoating may further comprise a layer comprising silicon nitride locatedbetween at least the glass substrate and the first transparentdielectric layer.

In the coated article of any of the preceding nine paragraphs, thecoating may further comprise a layer comprising zinc oxide and/or zincstannate located under and directly contacting the IR reflecting layer.

In the coated article of any of the preceding ten paragraphs, thecoating may further comprise a layer comprising an oxide of Ni and/or Crlocated over and directly contacting the IR reflecting layer.

In the coated article of any of the preceding eleven paragraphs, thecoated article may be thermally tempered.

In the coated article of any of the preceding twelve paragraphs, thecoated article may have a visible transmission of at least 50%, morepreferably of at least 60%, and even more preferably of at least 70%(e.g., measured monolithically).

The coated article of any of the preceding thirteen paragraphs may bemade by a method comprising sputter depositing the first transparentdielectric layer on the glass substrate; sputter-depositing the infrared(IR) reflecting layer (which may comprise silver, gold, or the like) onthe glass substrate, located over at least the first transparentdielectric layer; sputter-depositing the second transparent dielectriclayer on the glass substrate, located over at least the IR reflectinglayer; and wherein at least one of the first and second transparentdielectric layers is sputter-deposited in a manner, via metal or ceramictarget(s), so as to be amorphous or substantially amorphous, andcomprise an oxide of Ti and at least one of Sn, SnZn, Zr, Y, and Ba. Inthe method, the at least one of the first and second transparentdielectric layers may be sputter-deposited, so as to be amorphous orsubstantially amorphous, in an oxygen depleted atmosphere so that adifference in ionic radii for metals during sputtering causes latticedisorder leading to amorphous or substantially amorphous structure ofthe layer. During sputter depositing the amorphous or substantiallyamorphous layer comprising an oxide of Ti and at least one of Sn, SnZn,Zr, Y, and Ba, oxygen during the sputter depositing may be controlled,via control oxygen gas in the sputtering atmosphere and/or oxygen insputtering target material, so as to cause an average difference of atleast 15 pm (more preferably of at least 20 pm) in ionic radii betweenTi and at least one of Sn, SnZn, Zr, Y, and Ba and thus a latticedisorder leading to amorphous or substantially amorphous structure ofthe layer being sputter deposited. During sputter depositing theamorphous or substantially amorphous layer comprising an oxide of Ti andat least one of Sn, SnZn, Zr, Y, and Ba, the sputtering atmosphere maybe controlled so as to contain no more than 50% oxygen gas, morepreferably no more than 40% oxygen gas, and most preferably no more than35% oxygen gas, and a remainder of the gas may be argon gas and/or anyother suitable gas.

While the invention has been described in connection with what ispresently considered to be the most practical and preferred embodiment,it is to be understood that the invention is not to be limited to thedisclosed embodiment, but on the contrary, is intended to cover variousmodifications and equivalent arrangements included within the spirit andscope of the appended claims.

1-47. (canceled)
 48. A coated article including a coating supported by aglass substrate, the coating comprising: a first transparent dielectriclayer on the glass substrate; an infrared (IR) reflecting layercomprising silver on the glass substrate, located over at least thefirst transparent dielectric layer; a second transparent dielectriclayer on the glass substrate, located over at least the IR reflectinglayer; and wherein at least one of the first and second transparentdielectric layers is amorphous or substantially amorphous, and comprisesan oxide of Ti doped with at least one of Sn, SnZn, Zr, Y, and Ba, andwherein metal content of the amorphous or substantially amorphous layercomprises from about 70-99.5% Ti and from about 0.5-30% Zr (atomic %).49. The coated article of claim 48, wherein metal content of theamorphous or substantially amorphous layer comprises from about 80-99%Ti and from about 1-20% Zr (atomic %).
 50. The coated article of claim48, wherein metal content of the amorphous or substantially amorphouslayer comprises from about 87-99% Ti and from about 1-13% Zr (atomic %).51. The coated article of claim 48, wherein the amorphous orsubstantially amorphous layer has a refractive index (n) of at least2.12.
 52. The coated article of claim 48, wherein the amorphous orsubstantially amorphous layer has a refractive index (n) of at least2.20.